PROFESSORS warn mankind could die out because overcrowding could kill our mood for sex.
The population is expected to swell by 1 billion in just 12 years – but that’s all that will be growing.
A chilling study from the 1950s study suggests cramped mice dismissed sex, and spent most their energy on self grooming.
Scientist John B. Calhoun observed mice in a “utopia” with warmth, bedding, food and drink.
It caused the population to, initially, surge.
But the cramped conditions saw male mice become violent and savage, and females began neglecting their young.
The new generation of mice were called “the beautiful ones” due to their tendency too groom and beautify themselves instead of seeking a mate.
A book detailing the experiment, Tragedy in Mouse Utopia by JR Vallentyne, has sparked fears the same could happen with humans.
Economist Max Kummerow Ph.D admitted Calhoun’s work was “food for thought”.
He says: “We obviously tolerate living in cities of 20 million or more of us.
“But I do think this book offers important food for thought. Humans are violent. We have nuclear weapons.”
Meanwhile, there is another threat to our future, and our libidos – our mobile phones.
Doctors Jean Twenge and Heejung Park have published evidence that technology is out biggest turn off.
Researchers said the increased availability of social media, computer games and porn has given people other “pleasurable options”.
Adults are having sex eight times less a year than they did a decade ago.
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